Project Summary/Abstract Small nanoclusters of noble metals have emerged as promising fluorescent markers in nanomedicine applications, due to their high brightness, low toxicity and tunability. More recently, these materials have been implicated as having antimicrobial properties and can be targeted to multidrug resistant microbes. However, for silver nanoclusters (AgNCs), it is still problematic to delineate relative contributions of size, configuration, and environment on the optical properties, much less the antimicrobial mechanism. We aim to combine theoretical and experimental studies to understand the structure-property relationship in these tuned systems. It is proposed herein to (1) tune the optical properties of AgNCs using a refined DNA scaffolding protocol; (2) characterize the AgNCs to confirm their tuned optical properties (3) calculate the effects of the tuning protocol in the quantum confined regime for comparison to, and prediction of, additional tunable analogues. The outcomes of this project will contribute to the fundamental knowledge of new fluorophores.